Process of producing pistons.



A. WEBER.

PROCESS OF PRODUCING PISTONS.

APPLIOATION FILED NOV.20,1913.

Patented Aug. 11, 1914,

2 SHEETSSHEET 1 A. WEBER.

PROCESS OF PRODUCING PISTONS.

APPLIGATION FILED NOV.20, 1913. 1, 1 06 905. Patented Aug. 11, 1914,

2 SHEETSSHEET 2 [NYE/V7012,

WM 111 MMW' K To all 'wh am it m ay concern ion.

ALBERT WEBER, or CLEVELAND, 0:110, ASSIGNOR TO THE PEER-O MACHINE AND FOUNDRY COMPANY, or CLEVELAND, OHIO, A CORPORATION or 'OHIO.

PROCESS OF PRODUCING PISTONS.

Be it known that I, ALBERT \VEBER, a citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Processes of Producing Pistons, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention relates to processes of manufacturing. pistons of a type particularly adapted for use in internal combustion engines.

It is the purpose of this invention to produce a mold whereby an article of this character may be manufactured in such manner that the weight will be reduced to a minimum, the metal will be homogeneous, the annular piston wall will be of uniform thickness *lllll'OTlgllflllt its extent, and a maximum of strength in the finished article will he obtainable.

A further object of this invention is to enable an article of this kind to be produced in a particularly simple and inexpensive manner.

In the drawings forming part hereof, Figure 1 represents a perspective view, with parts broken away, of a piston produced in accordance with this invention; Fig. 2 a vertical sectional view through a flask section showing the piston patterns in place therein, with covers applied to the open upper ends of said patterns, the flask section being partly rammed; Fig. 3 represents a similar sectional view, showing the cores in place and the flask section completely rammed; Fig. 4 is a view, similar to Fig. 3, through the complete flask, the patterns being removed and the cope being applied with the parts in position for pouring.

In Fig. 1 there is shown a completed piston such as it is the aim of this process to produce The piston shown herein is of the trunk type and comprises a thin cylindrical wall 1 having the connecting rod sleeves 2 therein, the head 3, and the annular packing ring groove4, located preferably adjacent to the head.

' In the automobile art, it is a matter of great importance that the pistons, which Specification of Letters Patent.

Application filed November 20, 1913.

Patented Aug. ill, w ll. Serial No. 802,048.

operation as well as relieving the connected parts from unnecessary strain due to inertia. By the method described hereinafter, it is possible to cast the pistons and, in so doing, to employ a minimum amount of metal and reduce to a minimum the op ei-ations which must be performed upon the casting in order to convert it into the working piston.

In carrying out the invention, one or more 5 patterns A are placed within one of the flask speed. shall be made as light as possible, with the view of obtaining increased e fiiciency in i sections B of the mold, the section in the instance shown herein being the drag. The patterns are conveniently and preferably attached to a board 0. It will be noted that the drag B is of considerably greater depth than. the patterns and when jar-ramming is resorted to, the drag will be filled with. sand to a point below the tops of the patterns and the open upper ends of said patterns will be closed, as by means of the tapered plugs I) carried by a board E having a handle F whereby it may be manipulated. Assuming that jar-ramming is employed, after such preliminary ramming, the board E, with the attached plugs D, will be removed and any foreignv material that may be inside of the patterns will he removed, as by means of an air blast. The cores G are then introduced into the patterns. Each core is of such shape as to fit snugly the cylindrical inner surface of its pattern and each core is provided with a flaring extension g, preferably of inverted frusto-conical shape, the upper end or smaller end of the frustum merging with the cylindrical portion of the core and being connected thereto by an annular ledge g. This ledge not only protects the upper end of the pattern against the entrance of sand, but prevents the formation of a narrow lodge in the sand mold which would be liable to Crumble when the pattern is removed. When the cores have been inserted, the drag is filled and rammed by hand and the bottom board H is then applied. The"- drag is then inverted and the board C, with the attached patterns A, is removed. A flat cope I having its mold section therein is then applied to the upper end of the drag. The mold sections are indicated generally at K and L; and the latter section is shown as provided with the sprue hole M. The parts are now in position for pouring, with the cores G accurately positioned. within and uniformly spaced from the surrounding mold walls A. After the pouring operation, the castings are finished. This finishing, however is extremely simple because of the lmiforuuty in thickness of the casting and the tactv that it iu-cessary to remove so little of the casting other than that necessary to produce the ring groove 1-. The casting is true and even in thickness and the finishing may be done by grinding, thus eliminating the usual step of turning off the outside of the casting.

By the employment of the process described, it will be evident thatan annular casting has been produced whereof the side wall is a true even annulus; that, on account of the uniformity in the thickness of the wall, a'minimum amount of metal is necessary, wherefore the casting may be made much lighter than is possible by ordinary methods of production. A further and very great advantage arises from the fact that it is not necessary, after the finishing operation, to remove much of the skin of thecasting-the strongest part-in order to make the casting true. Furthermore, be- .cause of the uniformity in thickness, the casting may be made lighter, because such uniformity in thickness is attended with a corresponding increase in strength. Bysetting in the core when the pattern is partly rammed, the core is protected from injury. "Finally, by the process described herein, it is possible to produce the piston castings much more rapidly than is possible by ordinary methods.

lVhen jar ramming is employed, there is danger ofthe cores being broken by the preliminary ramming; hence the cores are not inserted until after the preliminary ramming operation. When the mold is rammed by hand, the cores will be applied to the patterns in the first instance and the mold may be rammed by hand without breaking or injuring the cores. WVith this exception,

the process will be performed in the same -manner as disclosed hereinbefore.

Having thus described my invention, what 1; The process of producing molds for pistons which consists in placing an annular pattern in a flask section; filling the said flask sect-ion with sand to a point below the bpenupper end of the pattern; then ramming;'then inserting in the pattern a core fitting accurately the inner wall of said pattern, the core having an outwardly flaring end in the flask section above the open end board and the attached pattern; and applying to the upper end of the flask section the se'cond flask section with its mold section itlireinz u 1 "1 2. The process of producing molds for pistons which comprises placing an annular pattern in the bottom of an inverted flask section; filling the said flask section with sand to a point below the open end of the pattern: then ramming; then inserting in the pattern a core fitting accurately the inner cylindrical wall of the pattern, the core having an outwardly flaring end in the flask section above the open end of the pattern; then filling and ramming the flask section; applying a bottom board to the upper end of the flask section, inverting the flask section and removing the pattern board and the attached pattern; and applying to the upper end of the flask section the second flask section with its mold section therein.

3. The process of producing molds for pistons which comprises applying to one end of a flask section a pattern plate with a hollow cylindrical pattern thereon; arranging the flask section, pattern and plate so that the open end of the pattern projects upwardly within the flask section: applying to the pattern a core which fits accurately the inner wall thereof and which is provided with an extension above the open end of the pattern; ramming the flask section with sand; inverting the flask section; removing the pattern; and applying a second flask section with its mold section to the upper end of'the first mentioned flask section.

l. The process of producing molds for cast pistons which comprises introducing into a flask section an annular pattern having its open end presented upwardly; placing within the pattern a core fitting snugly the inner surface of the pattern, the core having a locking extension above the open upper end of the pattern; and filling and ramming the flask section; removing the pattern.

5. The process of producing molds for cast pistons which comprises introducing into the bottom of a flask section an annular pattern having its open end presented upwardly; filling the flask section with sand to a point below the upper end of the pattern; ramming the sand; placing within the pattern a core fitting snugly the inner surface of the pattern, the core having an upwardly and outwardly flaring extension above the open upper end of the pattern; filling and rammingthe flask section; inverting the flask section and removing the pattern; and applying to the top of the flask section a sec ond flask section having its mold section therein.

6. The process of producing molds for cast pistons which comprises applying to one end of a flask section a board having an annular pattern thereon, the flask section being so arranged that the board shall be at the bottom thereof with the open end of the 7 pattern projecting upwardly; applying to the pattern a core fitting snugly the inner wall thereof, the core having a locking extension; filling and ramming the flask section, with the core in place; and separating the board and its attached pattern from the flask section.

7. The process of producing molds for east pistons which comprises attaching to the bottom of an inverted flask section a board having an annular pattern thereon; inserting into the pattern a core having a locking extension; filling and ramming the flask section whereby the core is firmly locked in the mold section in the flask section; inverting the flask section and removing the board therefrom, thereby drawing the pattern; and applying to the top of said flask section a second or cope section with its mold section therein.

8. The process of producing molds for east pistons which comprises applying to one end of a flask section a board having an annular pattern thereon, the flask sect-ion being so arranged that the board shall be at the bottom thereof with the open end of the board projecting upwardly; applying to the pattern a core fitting snugly the inner Wall thereof and having an inverted frusto-conical extension connected with the cylindrical portion of the core by an annular shoulder which is adapted to overhang the open upper end of the pattern; filling and ramming the flask section whereby the core is firmly locked in the mold section in the flask section; inverting the flask section and removing the board therefrom, thereby drawing the pattern; and applying to the top of said flask section a second or cope section with its mold section therein.

In testimony whereof, I hereunto afiix my signature in the presence of two witnesses.

ALBERT WEBER.

Witnesses MILTON BECK, W. D. SWEENY. 

